Conradson carbon ("Concarbon") number is a measure of the characteristic tendency of a petroleum feedstream to form coke during processing. Feedstreams having a lower Concarbon number are more economically desirable as refinery feeds than feedstreams having a higher Concarbon number.
Electrochemical processes have been used for removal of halogenated organic compounds, e.g., polychlorinated biphenyls in one phase organic systems see e.g., U.S. Pat. No. 5,102,510 and for removal of water soluble metals from aqueous streams, see e.g., U.S. Pat. No. 3,457,152. Petroleum streams are typically not halogen containing. Decreasing the Conradson carbon content of petroleum streams is more difficult to achieve because the hydrocarbon species are not readily water soluble. U.S. Pat. No. 5,514,252 discloses a process for electrochemically decreasing the Conradson carbon content of petroleum streams, but there is a continuing need for effective treatment methods, particularly ones in which enhanced rates of treatment at higher current efficiencies and/or lower electrolyte concentrations are possible. Applicants' invention addresses this need.